Illawarra Fly Tree Top Walk - Southern Highlands, NSW, Australia

Not all gum trees are the same

Two large eucalypt tree species grow in the forest along the Illawarra Fly. Brown Barrel or Eucalyptus fastigata is the most common, with rich brown bark on the trunk and smooth bark on the upper branches. Here and there along the walkway, where the branches hang close, you can have a good look at the buds and fruit. The other large eucalypt species, Gully Gum or Eucalyptus smithii, can be seen near the edge of the escarpment. It has a hard lower bark, with smooth bark higher up that falls off in long streamers and gets caught up in the branches.

Giants of the forest

At maturity and in ideal conditions, Brown Barrel (Eucalyptus fastigata) trees can grow more than 40 metres tall. This species' common name is based on the colour of the lower trunk or "barrel" of the tree, which is brown and stringy.

Most of the Brown Barrel trees in this area have regrown since the forest was logged last century. That is why they are roughly of the same size (and age) and why most of the tree trunks are still rather slender. With time, these huge trees will develop to their full potential, to become true forest giants.